Radical-7R Pulse CO-Oximeter Operator’s Manual
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O v e r v i e w
Acquisition System
The acquisition system converts the electrical signal provided by the sensor into a digital
signal. This format allows the signal to be processed by a computing device.
Signal Processing
The digital signal produced by the acquisition system is converted into a measurement that
corresponds to the respiratory parameter of interest. As shown in the figure on the previous
page, this can be performed by, for example, determining the digital signal envelope or out-
line which in turn may be utilized to determine the respiratory rate. In this way, a real-time,
continuous breath rate parameter can be obtained and displayed on a monitor which, in
many cases, may be real-time and continuous.
The respiratory cycle envelope signal processing principle is similar to methods that sample
airway gases and subsequently determine a respiratory rate.
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[3] Olsen, et al. Mechanisms of lung sound generation. Semin Respir Med 1985; 6: 171-179.
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